Method of manufacturing conical tubes.



No. 722,398. 4 PATENTED MAR. 10, 1903.

' E.BOGK.

METHOD OF MANUFACTURING CONIUAL TUBES.

' APPLICATION FILED MAY 20, 1901.

N0 MODEL. 2 SHEETS-SHEET 1,

, PATENTED MAR. 10, 1903. y E. BOGK. METHOD OF MANUFACTURING OONIOAL TUBES.

APPLICATION FILED MAY 20, 1901.

2 SHEETS-SHEET 2.

N0 MODEL.

UNITED STATES EMIL BOOK, OF DUSSFLDORF, GERMANY.

METHOD OF MANUFACTURING CONICAL TUBES.

SPECIFICATION formingpart of Letters Patent No. 722,398, dated March 10, 1903.

Application filed May 20, 1901.

To all whom it Htcty concern:

Be it known that I, EMIL BOOK, a subject of the King of Prussia, German Emperor, residing at No. 28 Humboldst rasse, Dusseldorf, in the Kingdom of Prussia, German Empire, have invented a new and useful Improved Method of Manufacturing Conical Tubes; and Ido hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved method of manufacturing conical tubes.

Hitherto conical tubes if not cast in a single piece have been made by riveting, welding, or folding of the edges of atapering plate, Figure 1, or plates, Figs. 2 and 3, bent to form a channel or gutter, in the latter case the conical tube being formed with longitudinal ribs,which impart greater rigidity to the finished tube and permit of it being more readily riveted. These methods of manufacturing conical tubes are subject to the great objection that the preliminary forming and pressing or rolling of long plates into channel form is difiicult, while, furthermore, the parts thus prepared are often so distorted after pressing as to render it impossible, or nearly so, to fit the said parts together.

Now this invention has for its object to obviate the above-mentioned objections and to provide an improved method whereby the manufacture of conical tubes is rendered more easy and expeditious.

According to myinvention I first secure the edges of suitably-cut tapering plates or a single plate, and then only shape the, same into a tubular form for .certain lengths at a time and in succession. To this end a mandrel of appropriate diameter is introduced, so as to open the plates and give them a tubular form, while at the same time an external mold partly or entirely surrounds the tube being formed.

I shall now proceed to describe my invention in detail with reference to the accompaing drawings, in which Figs. 1 and 2 show side elevations and sections of conical tubes manufactured, respectively, of one and of two strips, and Fig. 3 of a tube with longitudinal ribs. Fig. 4 illustrates in section on the line 4 4 of Fig. 5 a

the outer surface against the matrices.

conical tube in process of manufacture of one Serial No. 61,037. No model.)

strip or plate. Figs. 5, 4., and 4 are sectional views on the lines 5 5, M4, and 4 43, respectively, of Fig. 4;. Fig. 6 illustrates the method of fitting the two strips to one another when no longitudinal ribs are to be formed. Figs. 7, 8, and 9. illustrate methods of fitting strips so as to form tubes with longitudinal ribs. Figs. 10, 11, 12, and 13 show inform of diagrams the parts in detail by means of which the strips or plates are held during the operation.

As is shown by Fig. 4, a tapering plate R is first bent at one end in such a manner as to allow the edges to be secured together either permanently by riveting or temporarily by any other convenient means. The plate R is gradually bent from a straight into almost round or circular form,'Figs. 5,

4 and 4 with the edges overlapping to enable them to be connected together. The prepared tube end is correctly rounded into the required tubular form by means of a mandrel D, corresponding to the internal width of the tube and being driven into the tube in the direction of the arrow, while two molds or matrices M M, Figs. 4, 5, surround the tube being manufactured, so as to prevent the joint being destroyed and to enable the correct form to be obtained by pressing After having thus finished one portion of the tube the mandrel is withdrawn. The formation of the next portion of the tube is then proceeded with by using a mandrel of slightlylarger diameter in conjunction with a corresponding pair of matrices, the operation and finishing of this second portion of the tube being exactly similar to that described with reference to the first portion. After the second portion of the tube has been finished the next portion, &c., is completed until the entire conical tube is completed.

The tube to be manufactured in accordance with thisimproved method may also be formed of two strips or plates R, which have previously been bent to fit together, as shown in Fig. 6, or to be riveted together and which are then formed into the proper tube by means of successive mandrels and corre sponding matrices, as represented in Figs. 4 and 5. For manufacturing tubes with longitudinal ribs the two strips or plates are placed together with or without a fillingpiece 70 at the edges, and the latter are then firmly secured together by riveting, welding, beading, or otherwise, Figs. 7 to 9. The strips R are then opened by means of suitably tapered and pointed mandrels, so as to form a circular tube, in the manner previously described, the mandrel of largest diameter being introduced first, while the remaining mandrels follow in successive order down to the smallest one. The tube portion under operation may be surrounded by a divided matrix completely fittingit, or, if desired, cheeks q q only may be employed to hold the edges of the strips, Fig. 10 and 11. In the latter case the cheeks form a divided pair of matrices,which instead of completely surrounding the tube being manufactured only partly surround the edges which subsequently form the ribs of the tube, this being effected somewhat in the manner of a vise action, so as to prevent the joint being opened. These divided clamping-matrices act in conjunction with the advancing mandrel to open the tube by being moved toward each other simultaneously therewith in the direction of the arrows Z, Fig. 10, through the efforts of an appropriate external force P. In this mannor the plates are more readily opened and shaped into a circular form.

The method hereinbefore described for the manufacture of conical tubes may be modified in so far as to cause the edges of the properly-cut strips or plates R to be engaged between pairs of matrices or checks M M or q q, respectively, extending over the entire length of the tubes. The matrices thus extending over the full length of the strips or plates previously to the introduction of the mandrel are moved toward each other to suit the diameter of the mandrel subsequently used, so as to cause the said strips or plates to assume a somewhat-circular form, as indicated by Figs. 12 and 13, the matrices being either cheeks, as in Fig. 12, or of complete tubular form, as in Fig. 13. The strips or plates thus previously molded into a nearly-circular shape are completely opened and shaped by means of various mandrels in the manner hereinbefore described, the graduated operation of shaping from the flat into a circular form being unnecessary. It may,

however, be advantageous to bend the strips slightly along the middle before or slightly separate or open them after engaging in the matrices, so as to more readily cause them to bend outward. For the lattermethod the mandrels require less power for forming the tubes than in the previously-described method for the reason that the mandrels are no longer required to open and shape, but have only to'finally round the tubes, and therefore the mandrels may be made longer and the stepwise shaping of the tubes can be efiected in greater length. Tubes of somewhat-limited length and of thin material may for example, be manufactured with a single mandrel, whereby the cost of manufacture is greatly reduced.

Having thus described my invention, what I claim is 1. The method of manufacturing conical tubes of one or more tapering plates which consists in holding the edges of the plate or plates and subjecting the plate or plates for certain lengths to successive internal pressure, by which said plates are expanded and given a conical shape, substantially as and for the purpose described.

The method of manufacturing conical tubes of one or more tapering plates which consists in holding the edges of the plate or plates and subjecting the plate or plates for certain lengths to successive internal pressure by which said plates are expanded and given a conical shape and limiting the expansion by external resistance, substantially as and for the purpose described.

3. The method of manufacturing conical tubes with longitudinal ribs of one or more tapering plates which consists in holding the edges of the plate or plates, subjecting the plate or plates to certain lengths to successive internal pressure by which said plates are expanded and given a conical shape and during the said expanding pressure subjecting plate or plates to lateral pressures, whereby the edges are caused to move inward, substantially as and for the purpose described.

t. The method of manufacturing conical tubes with longitudinal ribs of one or more tapering plates which consists in holding the edges of the plates along the entire length of the tube to be produced, subjecting the edges of the plates along the entire length of the tube to lateral pressures, whereby said edges are caused to move inward and producing internal pressure by which the expanded plates are given the exact conical shape.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

' EMIL BOOK. WVitnesses:

WILLIAM Essnnwnnv, H. DEDERIOH. 

